exchanges: Initial context propagation (#744)

* gct: phase one context awareness pass

* exchanges: context propagation pass

* common/requester: force context requirement

* gctcli/exchanges: linter fix

* rpcserver: fix test using dummy rpc server

* backtester: fix comments

* grpc: add correct cancel and timeout for commands

* rpcserver_test: add comment on dummy server

* common: deprecated SendHTTPGetRequest

* linter: fix

* linter: turn on no context check

* apichecker: fix context linter issue

* binance: use param context

* common: remove checks as this gets executed before main

* common: change mutex to RW as clients can be used by multiple go routines.

* common: remove init and JIT default client. Unexport global variables and add protection.

* common: Add comments

* bithumb: after dinner mints fix

cmd/documentation/documentation.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	"context"
 	"encoding/json"
 	"errors"
 	"flag"
@@ -8,6 +9,7 @@ import (
 	"html/template"
 	"io/ioutil"
 	"log"
+	"net/http"
 	"os"
 	"path/filepath"
 	"strings"
@@ -162,7 +164,7 @@ func main() {
 		if verbose {
 			fmt.Println("Fetching repository contributor list...")
 		}
-		contributors, err = GetContributorList(config.GithubRepo)
+		contributors, err = GetContributorList(config.GithubRepo, verbose)
 		if err != nil {
 			log.Fatalf("Documentation Generation Tool - GetContributorList error %s",
 				err)
@@ -432,9 +434,19 @@ func GetTemplateFiles() (*template.Template, error) {
 
 // GetContributorList fetches a list of contributors from the github api
 // endpoint
-func GetContributorList(repo string) ([]Contributor, error) {
+func GetContributorList(repo string, verbose bool) ([]Contributor, error) {
+	contents, err := common.SendHTTPRequest(context.TODO(),
+		http.MethodGet,
+		repo+GithubAPIEndpoint,
+		nil,
+		nil,
+		verbose)
+	if err != nil {
+		return nil, err
+	}
+
 	var resp []Contributor
-	return resp, common.SendHTTPGetRequest(repo+GithubAPIEndpoint, true, false, &resp)
+	return resp, json.Unmarshal(contents, &resp)
 }
 
 // GetDocumentationAttributes returns specific attributes for a file template